Fracture Around Ankle

prepared:

Dr. Amanj M. Mustafa

Supervised by.

Ass. Prof. Dr.Omer Barawi

Significance of Ankle Fractures

• Most common weight-bearing fracture

• Bimodal distribution

– Men 15-24

– Women over 60

– Not related to osteoporosis

– Related to obesity

• Ankle is a three bone joint composed of the tibia , fibula an talus

• Talus articulates with the tibial plafond superiorly , posterior malleolus of the tibia posteriorly and medial malleolus medially

• Lateral articulation is with malleolus of fibula

ANKLE ANATOMY

Lateral Ligaments

Medial Ligaments

The joint is considered saddle-shaped with the dome itself is wider anteriorly than posteriorly, and as the ankle dorsiflexes, the fibula rotates externally through the tibiofibular syndesmosis

Biomechanics…• Complex motion• Normal ROM:

• ~20 degrees of extension • ~40 degrees of flexion• ~30 degrees of invertion• ~15 degrees of evertion

• At least 10 degrees of dorsiflexion is needed for normal gait

• 1 mm of lateral talar shift decreases tibiotalar surface contact up to 40%

Physical Examination…

• Note obvious deformities• Neurovascular exam• Pain to palpation of malleoli and ligaments• Palpate along the entire fibula• Pain at the ankle with compression

– syndesmotic injury

• Examine the hindfoot and forefoot for associated injuries

X-ray

• AP, Lateral and Mortise views of the ankle

• AP and lateral of tibia

Normal ankle (AP view)

Normal ankle (Mortise view)

Normal ankle (Lateral view)

Anteroposterior View

• Tibiofibular overlap– <10mm implies syndesmotic

injury

• Tibiofibular clear space – >5mm implies syndesmotic

injury

• Talar tilt– >2mm is considered

abnormal

Mortise View

AP view of ankle with foot internally rotated(15 degree)

Abnormal findings:– medial joint space

widening– tibia/fibula overlap

<1mm

Lateral View

• Posterior malleolus fracture

• Subluxation of the talus • Angulation of distal fibula• Talus fractures• Calcaneus fractures

Other Imaging Modalities• Stress Views

– Gravity stress view – Manual stress views

• CT– Joint involvement– Posterior malleolar

fracture pattern– Pre-operative

planning– Evaluate hindfoot

and midfoot if needed• MRI

– Ligament and tendon injury

– Talar dome lesions– Syndesmosis injuries

Classification Systems

• Lauge-Hansen

• Danis-Weber

• AO Classification

TYPES OF FRACTURE LINE

Pull-off or Push-off fracturesThe shape of a fracture indicates which forces were involved.An oblique or vertically oriented fracture indicates 'push-off'.A transverse or horizontal fracture is the result of a 'pull-off'. On the left image the lateral malleolus is pushed off by exorotation of the talus. On the right image the medial malleolus is pulled off by the medial collateral ligament due to pronation of the foot.

stability

SUPINATION-ADDUCTION• It occurs in about 20-25% of all ankle fractures. • The foot is fixed on the ground in supination when an

adduction force is applied to the talus.• Stage 1

Supination results in a tear of the lateral collateral ligament or an avulsion fracture of the lateral malleolus below the level of the tibial plafondStage 2More talar tilt results in the medial malleolus being pushed off in a vertical or oblique way .

SUPINATION-EXT.ROTATION• This is the most common type and occurs in

about 60-70% of all ankle fractures.• The foot is fixed on the ground in supination and

an exorotation force is applied to the talus.

SUPINATION-EXT.ROTATION• Stage 1: Rupture of anterior inferior tibiofibular ligament.

• Stage 2: Oblique fracture or spiral fracture of the lateral malleolus.

• Stage 3: Rupture of post tibiofibular ligament or fracture of posterior malleolus of tibia.

• Stage 4: Transverse (sometimes oblique) fracture of Tibial malleolus.

supination -exorotation injury the events take place in a clockwise manner

Pronation-external rotation• This is seen in approximately 20% of ankle

fractures. The foot is fixed on the ground in pronation when an exorotation force is applied to the talus

Stage 1 Transverse medial malleolus fx distal to mortise

Stage 2 Posterior malleolus fx or posterior tibio-fibular ligament

Stage 3 Fibula fracture, typically proximal to mortise, often with a butterfly fragment

Pronation-Abduction

1

2 3

Pronation-Abduction

Medial injury: tranverse to short oblique medial malleolar fracture

Lateral Injury: comminuted impaction type distal lateral malleolar fracture

Danis-Weber Classification• Based on location and appearance of fibula fracture

• Type A– Below syndesmosis– Internal rotation and adduction

• Type B– At level of syndesmosis– External rotation leads to oblique fracture

• Type C– Above syndesmosis– Syndesmotic injury

• Medial and posterior malleolar fractures, deltoid ruptures may occur with any of these

Stages of Exorotation

Exorotation of the talus.

Continuing exorotation of the talus will rupture the anterior tibiofibular ligament

Continuing force will fracture the fibula at the level of the joint in a Weber B-fracture or above the level of the syndesmosis in a Weber C-fracture.

Further posterolateral displacement of the lateral malleolus by the talus results in rupture of the posterior syndesmosis or avulsion of the malleolus tertius.

Finally the medial collateral ligament may rupture or the medial malleolus may avulse.

Alpha-Numeric Code

AO classification

Tibia =4

Malleolar segment =4

Infrasyndesmotic=44A

Suprasyndesmotic=44C

Transsyndesmotic=44B

+

Alpha-Numeric Code

Infrasyndesmotic=44A

Alpha-Numeric Code

Transsyndesmotic=44B

Alpha-Numeric Code

Suprasyndesmotic=44C

SALTR

Straight Above

(metaphysis)

Lower

(epiphysis)

T hrough

Physis

Ram

(Crush)

Initial Managment• Compression dressing, splint, and

elevation

• Closed reduction – Hematoma block– Conscious sedation

• Early Surgery– Unstable fractre– No soft tissue compromise

(blisters, severe swelling)– Open fractures

• Delayed treatment– Stable in splint– Soft tissues need to recover

• Pain control

Medial Malleolar Fractures

• Nondisplaced fractures may be treated nonoperatively

• Displaced fractures require anatomic reduction and fixation

• High nonunion rate

Lateral Malleolus Fractures

• Nonoperative managmement

– 2-3 mm displacement– NO medial widening or

syndesmotic injury– Cast or boot

immobilization 6 wks– Follow closely!– Superior results

Surgical Indications

• Bimalleolar / trimalleolar fractures

• Syndesmotic disruption

• Talar subluxation• Joint incongruity /

articular stepoff

• Lateral Malleolus

– Reduce first– Proximal fragment (shaft) needs reduction– 3 bicortical screws into proximal fibula– Unicortical screws into intra-articular portion– Be certain fibula is out to length

• Medial malleolus– Open reduction– Remove interposed soft tissue and

intraarticular fragment– Anti-glide plate for vertical fractures

Medial Malleolus Fixation

Posterior Malleolus

• Repair if >25% of articular surface

• Reduce by ankle dorsiflexion

• Clamp through fibular incision

• Anterior lag screws

Maissoneuve Fracture

• Fracture of proximal 1/3 of fibula

• +/- medial malleolar fracture

• Pronation-external rotation mechanism

• Requires reduction and stabilization of syndesmosis

Maissoneuve Fracture

• Fracture of proximal 1/3 of fibula

• +/- medial malleolar fracture

• Pronation-external rotation mechanism

• Requires reduction and stabilization of syndesmosis

• Fracture of distal tibial metaphysis– Often comminuted– Often significant other injuries

• Mechanism– Axial load– Position of foot determines injury

• Treatment– Unstable– X-ray tib/fib & ankle

Pilon (tibial plafond) fractures

Source:Rosen

Tillaux Fracture

Fracture of the anterolateral tibial epiphysis

Mechanism Avulsion of epiphyseal

fragment due to the strong anterior tibiofibular ligament

Salter-Harris 3 injury External rotational force

across the ankle

Commonly seen in adolescents

Treatment: ORIF

Postoperative Care

• Well padded splint immobilization

• Ice and elevation• Non weight bearing

for 6 weeks– Early weight bearing

possible

• Early conversion to brace and ROM

complications

• EarlyVascular injuryWound breakdown

and infection

• LateIncomplete

reducionNon-unionJoint stiffnessAlgodystrophyOA change

References:

• Campbell

• Apley

• Practical fracture treatment-McRae

The End

Thanks!